MALFORMATIONS OF THE VERTEBRAL BODIES AND THE RIBS ASSOCIATED TO SPINAL DYSRAPHISM WITHOUT SPINA-BIFIDA IN A PEKINGESE DOG

A Pekingese dog with hemivertebrae, rib malformations and spinal cord dysraphism without spina bifida was presented. Two types of hemiverteb rae were seen: bilateral and unilateral. Thoracic hemivertebrae were a ssociated with fused ribs and rudimentary ribs. Spinal dysraphism cons isted of polycavitary syringomyelia in the dorsal and lateral funiculi , hydromyelia and anomalies of the dorsal median septum and median fis sure, associated to lumbar and sacral hemivertebrae. Cauda equina agen esia was also present. To conclude, the dog showed two malformations f rom different embryonic origins. Vertebral and rib malformations are o f meso-dermic origin and spinal dysraphism is of ectodermic origin. A possible common mechanism responsible for both anomalies is discussed.